code: def test_inverse_transform_HaveHandleMissingValueAndHandleUnknownReturnNan_ExpectBestInverse(
      self,
  ):
      train = pd.DataFrame({"city": ["chicago", np.nan]})
      test = pd.DataFrame({"city": ["chicago", np.nan, "los angeles"]})
      expected = pd.DataFrame({"city": ["chicago", np.nan, np.nan]})
  
      enc = encoders.OneHotEncoder(
          handle_missing="value", handle_unknown="return_nan"
      )
      enc.fit(train)
      result = enc.transform(test)
      original = enc.inverse_transform(result)
  
      pd.testing.assert_frame_equal(expected, original)
  
imports: import pandas
  from unittest import TestCase
  import numpy
  import tests.helpers
  import category_encoders
label_desc: Use image node_id 23 for calling the TestOneHotEncoderTestCase obj's underlying member method code with example usage: obj.test_inverse_transform_HaveHandleMissingValueAndHandleUnknownReturnNan_ExpectBestInverse() without return types